如何修复Python代码中Elif语句内添加input产生的语法错误

问题原因 #

你代码的语法错误出现在y == "engineering"的判断分支中：
你错误使用了双等号==做变量赋值操作，该行代码z == input("Enter Stream: ")里的==是比较运算符，仅用于判断两个值是否相等，给变量z赋值需要使用单等号=。

解决方案 #

仅修改这一行的运算符即可，原有其他逻辑完全不需要改动：

x = input("Enter your name: ")
y = input("Enter your field: ")
print("Hello %s,You have a very interesting Field" % x)
print("Here are the future options for all the careers related to %s:"% y)
if y == "commerce":
    print("A.Chartered accountant\nB.Civil Services\nC.Accountant\nD.company Secretary\nE.Financial Analyst\nF.Auditor")
elif y == "biology":
    print("A.Doctor\nB.pharmacist\nC.Chemist\nD.Scientist")
elif y == "engineering":
    # 把原来的比较运算符==改成赋值运算符=即可
    z = input("Enter Stream: ")
    if z == "Mechanical":
        print("Mechanical Engineer")
    elif z == "computer science":
        print("A.Software Engineer\nB.Data Scientist\nC.Programmer")
else:
    print("I suppose you've entered Arts,YOu can opt for a career in\nA.IAS\nB.Music\nC.Political Science")

内容的提问来源于stack exchange，提问作者Aditya Singh